[CentOS] Regarding LARGE number of files in a folder in linux

Fri Jul 10 17:31:29 UTC 2009
Bob Hoffman <bob at bobhoffman.com>

> >
> > I would like to know what you do about the number of files in a 
> > folder, or if that is a concern. I think there is a limitation or a 
> > slow down if it gets to big, but what is optimal (if necessary)
> > SO what is best for file management and system resources?
> Using hash_index on ext3 or a hashing file system helps... 
> but in many such contexts, I've found if you can do a 
> multi-level directory hashing scheme (compute some 
> reproducible hash on a file name or user name/ID) and index 
> into a directory structure, this can help.
> -Alan

I set up using an ext3 and with centos I believe that is 4blocks which has a
8tb size limit overall.
However, I believe that is per logical drive.
Also, the number of total files per logical drive is some strange formula or
Volume size divided by 2 to the 23rd power...but not sure, it may be size /2
and then to the 23rd power.
That is a lot of files I think.
32,000 is the max sub directory count for a directory.

I am going with a max size of 1000 files per folder and a max sub directory
for, let's say an image folder, of 10,000. I think this will keep the
application I am building fine with most computers.

For my own sites, I think when approacing a huge volume it will be time to
just get some bigger drives with a different file system to host those
specific directories and that should solve it all.

The only way, I can see, to not slow the computer down is limit to number of
files in a directory and number of folders in a directory (such as no more
than 1000 1st tier sub directories in the image folder. 
And tying to make sure it is eiter folders or files in a folder, not both
should help.

OF course it would be nice to be able to benchmark the process by number of
files, sub  directories, and files per sub directory....there might be a

I think that is the only way to handle it, at least in a small system
without large drives and using ext3.

Thanks for all the input.